Preheat your oven to 350°F (175°C) to ensure it’s hot and ready for your cookies.
In a large mixing bowl, combine the room temperature butter, granulated sugar, and brown sugar. Beat on medium speed until light and fluffy, about 2-3 minutes.
Add the egg and vanilla extract to the mixture and mix until fully incorporated, scraping down the sides of the bowl as needed.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add this dry mixture to the wet ingredients, mixing just until combined.
Gently fold in the coarsely chopped white chocolate, milk chocolate, dried tart cherries, and pecans for even distribution.
Using a cookie scoop or tablespoon, drop rounded balls of dough onto a baking sheet lined with parchment paper, spacing them about 2 inches apart. Bake for 10-12 minutes, or until the edges are lightly golden.
Let the cookies cool on the baking sheet for about 5 minutes before transferring them to a cooling rack.